An orifice spillway is used where incoming sediment concentration is high. To ensure the safety of a dam structure, various components of orifice spillways need to be designed carefully. A physical model is best suited for visualizing and analyzing the flow over the spillway, upstream and downstream flow conditions, and the performance of the energy dissipation system. Numerical simulation methods are often used to arrive at a preliminary design and save time in model studies. To investigate the hydraulic characteristics of an orifice spillway, a physical hydraulic model, and numerical studies are presented in this paper. Hydraulic model tests were carried out on a 1:45 scale 2-D sectional model. The Computational Fluid Dynamics (CFD) software Flow-3D was used for numerical studies for modeling flow over an orifice spillway. To validate the numerical model, data such as flow conditions, discharging capacity, pressure distribution along the bottom profile of the sluice and spillway, velocity, and water surface profile were computed. A numerical model developed based on physical model studies was validated by using experimental values of pressures, water surface profiles, and discharge characteristics. The numerical models were able to accurately simulate the various hydraulic parameters of spillway flows since the simulated values were close to the experimental results. In the case of parametric studies, this model can be used quite efficiently as an initial investigation of spillway flows, thereby eliminating the need for repeated physical model studies with structural modifications, resulting in saving time and money.